I really think the etymology given here is incorrect.If you put "Jelani" into the easily accessible online Swahili-English dictionaries, those that have it at all say it means "jail."If you put "mighty" into these dictionaries, the Swahili words you get are makuu, imara, chakari, hasa, and sana."Strength" and "great" are two other words which Jelani is often said to mean in Swahili. If you put "strength" into the English-Swahili dictionaries, you get nguvu, nishati, tani, afya, kiume, afia, bavu, imara, kibavu, makadara, maume, mbavu, rai, siha, sulubu, tambo, ukali, ukalifu, ushupavu, ukabiti, and uthubutu -- 21 possibilities and none of them anything like "Jelani"! For "great" you get kubwa, mkubwa, kuu, mkuu, makubwa, makuu, vikubwa, mwingi, wakuu, adhimu, bora, kabambe, kikabaila, tukufu, safi, kikuu, mikuu, vikuu, and aali. If "Jelani" means anything like "mighty", "strength", or "great" in Kiswahili, it must be a really obscure word. I believe Jelani is the Swahili equivalent of Arabic Gīlānī or Jīlānī, originally part of a very famous Sufi saint whose full name according to today's Wikipedia is Muḥyī-al-Dīn Abū Muḥammad b. Abū Sāleh ʿAbd al-Qādir al-Gīlānī al-Hasani wa'l-Husayni, often shortened to ʿAbd al-Qādir al-Jīlānī. He lived 1077-1166. The book "Islamic Names" by Annemarie Schimmel (Edinburgh University Press, 1989) gives examples of several names from different Islamic cultures based on parts of al-Jīlānī's name. There even are many names based on "ghauth-i a'zam", his epithet which means "the greatest help", which is perhaps where the mistaken idea that the name means "great" or "mighty" comes from. "Al-Jīlānī" in reality is a part of this man's name which just refers to the place of his birth, Gilan province in northwestern Iran along the south shore of the Caspian Sea. The place name seems to be very ancient and goes back to one of the terms for the people who first settled there (Gelae in Latin, Gilites in English) and is probably one of those extremely ancient ethnic terms for which the original meaning in unknown. [noted -ed]
If you put "Jelani" into the easily accessible online Swahili-English dictionaries, those that have it at all say it means "jail."
If you put "mighty" into these dictionaries, the Swahili words you get are makuu, imara, chakari, hasa, and sana.
"Strength" and "great" are two other words which Jelani is often said to mean in Swahili. If you put "strength" into the English-Swahili dictionaries, you get nguvu, nishati, tani, afya, kiume, afia, bavu, imara, kibavu, makadara, maume, mbavu, rai, siha, sulubu, tambo, ukali, ukalifu, ushupavu, ukabiti, and uthubutu -- 21 possibilities and none of them anything like "Jelani"! For "great" you get kubwa, mkubwa, kuu, mkuu, makubwa, makuu, vikubwa, mwingi, wakuu, adhimu, bora, kabambe, kikabaila, tukufu, safi, kikuu, mikuu, vikuu, and aali.
If "Jelani" means anything like "mighty", "strength", or "great" in Kiswahili, it must be a really obscure word.
I believe Jelani is the Swahili equivalent of Arabic Gīlānī or Jīlānī, originally part of a very famous Sufi saint whose full name according to today's Wikipedia is Muḥyī-al-Dīn Abū Muḥammad b. Abū Sāleh ʿAbd al-Qādir al-Gīlānī al-Hasani wa'l-Husayni, often shortened to ʿAbd al-Qādir al-Jīlānī. He lived 1077-1166.
The book "Islamic Names" by Annemarie Schimmel (Edinburgh University Press, 1989) gives examples of several names from different Islamic cultures based on parts of al-Jīlānī's name. There even are many names based on "ghauth-i a'zam", his epithet which means "the greatest help", which is perhaps where the mistaken idea that the name means "great" or "mighty" comes from.
"Al-Jīlānī" in reality is a part of this man's name which just refers to the place of his birth, Gilan province in northwestern Iran along the south shore of the Caspian Sea. The place name seems to be very ancient and goes back to one of the terms for the people who first settled there (Gelae in Latin, Gilites in English) and is probably one of those extremely ancient ethnic terms for which the original meaning in unknown. [noted -ed]